• MeSH
• cirkadiánní rytmus MeSH
• pohybová aktivita fyziologie   MeSH
• psi MeSH
• Check Tag
• psi MeSH

We describe a modification of epifluorescence microscopes that allows quantitative widefield imaging of samples labeled by upconverting nanoparticles (UCNP). A top-hat illumination profile on the sample was achieved with a 980-nm laser diode by using tandem microlens arrays, a moving diffuser and a telescope, which adjusts the top-hat area to the field of view. Illumination homogeneity is a critical factor for imaging of UCNP since the intensity of their luminescence typically scales with the second power of the excitation intensity. Our illuminator is combined with the epifluorescence attachment of the microscope, allowing easy switching between observation of UCNP and traditional fluorescent dyes. Illumination profile homogeneity of about 98% was measured for objectives with magnification from 4× to 100×, and the top-hat profile was also obtained with phase contrast objectives. We demonstrate capability of the illuminator by evaluating in vitro uptake of UCNP encapsulated in oleyl-hyaluronan micelles into breast cancer cells. Micelles bearing the targeting peptide were about an order of magnitude more efficient than nontargeted micelles.

• MeSH
• fluorescenční barviva MeSH
• fluorescenční mikroskopie přístrojové vybavení   MeSH
• lasery * MeSH
• lidé MeSH
• luminiscence MeSH
• nádorové buněčné linie MeSH
• nanočástice metabolismus   ultrastruktura   MeSH
• osvětlení MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

• MeSH
• hygiena práce MeSH
• infračervené záření MeSH
• lasery MeSH
• osvětlení MeSH
• světlo MeSH
• ultrafialové záření MeSH
• zrak genetika   MeSH

• MeSH
• bezpečnost vybavení normy   přístrojové vybavení   MeSH
• bezpečnost ekonomika   normy   zákonodárství a právo   MeSH
• chemické inženýrství normy   přístrojové vybavení   MeSH
• elektřina škodlivé účinky   MeSH
• lasery normy   škodlivé účinky   MeSH
• lidé MeSH
• osvětlení normy   přístrojové vybavení   škodlivé účinky   MeSH
• pracoviště normy   zákonodárství a právo   MeSH
• pracovní lékařství metody   normy   trendy   MeSH
• prostředí kontrolované MeSH
• referenční standardy MeSH
• spotřebitelská bezpečnost produktů normy   zákonodárství a právo   MeSH
• zdraví MeSH
• Check Tag
• lidé MeSH
• Geografické názvy
• Česká republika MeSH

• MeSH
• elektromagnetická pole škodlivé účinky   MeSH
• environmentální zdraví normy   MeSH
• formální sociální kontrola MeSH
• lasery normy   škodlivé účinky   MeSH
• osvětlení normy   MeSH
• prostředí kontrolované MeSH
• rizikové faktory MeSH
• životní prostředí MeSH

• Konspekt
• Hygiena. Lidské zdraví
• NLK Obory
• environmentální vědy

The potential of organic semiconductor based devices for light generation is demonstrated by the commercialisation of display technologies using organic light emitting diode (OLED). In OLED, organic materials plays an important role of emitting light once the current is passed through. However OLED have drawbacks whereby it suffers from photon loss and exciton quenching. Organic light emitting transistor (OLET) emerged as a new technology to compensate the efficiency and brightness loss encountered in OLED. The structure has combinational capability to switch the electronic signal such as the field effect transistor (FET) as well as to generate light. Different colours of light could be generated by using different types of organic material. The light emission could also be tuned and scanned in OLET. The studies carried out in this paper focuses on investigation of fabricated MEH-PPV based OLED and also OLET via current voltage characteristics. These studies will continue with a view to develop an optimised MEH-PPV based OLET.

• MeSH
• analýza selhání vybavení MeSH
• design vybavení MeSH
• elektrická vodivost MeSH
• elektronické tranzistory * MeSH
• organické látky chemie   MeSH
• osvětlení přístrojové vybavení   MeSH
• polovodiče * MeSH
• transport elektronů MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH

• MeSH
• cirkadiánní rytmus fyziologie   MeSH
• dekompresní nemoc prevence a kontrola   MeSH
• hyperbarická oxygenace * metody   trendy   využití   MeSH
• hypoxie metabolismus   patofyziologie   MeSH
• klinické zkoušky jako téma MeSH
• kongresy jako téma MeSH
• lasery škodlivé účinky   MeSH
• letecké a kosmické lékařství dějiny   trendy   MeSH
• letectví MeSH
• lidé MeSH
• otrava oxidem uhelnatým rehabilitace   MeSH
• potápění škodlivé účinky   MeSH
• Check Tag
• lidé MeSH

Synchronized cultures of the green alga Chlamydomonas reinhardtii were grown photoautotrophically under a wide range of environmental conditions including temperature (15-37 °C), different mean light intensities (132, 150, 264 μmol m⁻² s⁻¹), different illumination regimes (continuous illumination or alternation of light/dark periods of different durations), and culture methods (batch or continuous culture regimes). These variable experimental approaches were chosen in order to assess the role of temperature in the timing of cell division, the length of the cell cycle and its pre- and post-commitment phases. Analysis of the effect of temperature, from 15 to 37 °C, on synchronized cultures showed that the length of the cell cycle varied markedly from times as short as 14 h to as long as 36 h. We have shown that the length of the cell cycle was proportional to growth rate under any given combination of growth conditions. These findings were supported by the determination of the temperature coefficient (Q₁₀), whose values were above the level expected for temperature-compensated processes. The data presented here show that cell cycle duration in C. reinhardtii is a function of growth rate and is not controlled by a temperature independent endogenous timer or oscillator, including a circadian one.

• MeSH
• buněčné dělení fyziologie   MeSH
• Chlamydomonas reinhardtii cytologie   růst a vývoj   MeSH
• kultivované buňky MeSH
• světlo MeSH
• teplota MeSH
• tma MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Perinatal ischemic stroke is a leading cerebrovascular disorder occurring in infants around the time of birth associated with long term comorbidities including motor, cognitive and behavioral deficits. We sought to determine the impact of perinatal induced stroke on locomotion, behavior and motor function in rats. A photothrombotic model of ischemic stroke was used in rat at postnatal day 7. Presently, we induced two lesions of different extents, to assess the consequences of stroke on motor function, locomotion and possible correlations to morphological changes. Behavioral tests sensitive to sensorimotor changes were used; locomotion expressed as distance moved in the open field was monitored and histological changes were also assessed. Outcomes depicted two kinds of lesions of different shapes and sizes, relative to laser illumination. Motor performance of rats submitted to stroke was poor when compared to controls; a difference in motor performance was also noted between rats with small and large lesions. Correlations were observed between: motor performance and exposition time; volume ratio and exposition time; and in the rotarod between motor performance and volume ratio. Outcomes demonstrate that photothrombotic cerebral ischemic stroke induced in early postnatal period and tested in adulthood, indeed influenced functional performance governed by the affected brain regions.

• MeSH
• červeň bengálská * MeSH
• cévní mozková příhoda etiologie   patologie   patofyziologie   psychologie   MeSH
• chování zvířat * MeSH
• intrakraniální trombóza etiologie   patologie   patofyziologie   psychologie   MeSH
• krysa rodu rattus MeSH
• lasery * MeSH
• metoda rotující tyčky MeSH
• modely nemocí na zvířatech MeSH
• mozek patologie   patofyziologie   MeSH
• pohybová aktivita * MeSH
• potkani Wistar MeSH
• psychomotorický výkon * MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• srovnávací studie MeSH

Arctic microalgae experience long periods of continuous darkness during the polar night, when they are unable to photosynthesize. Despite numerous studies on overwintering strategies, such as utilization of stored energy products, formation of resting stages, reduction of metabolic rates and heterotrophic lifestyles, there have been few attempts to assess the in situ physiological state and restoration of the photosynthetic apparatus upon re-illumination. In this study, we found diverse and active marine phytoplankton communities during the polar night at 78°N. Furthermore, we observed rapid changes (≤20 min) in the efficiency of photosynthetic electron transport upon re-illumination. High photosynthetic capacity and net primary production were established after 24 h of re-illumination. Our results suggest that some Arctic autotrophs maintain fully functional photosystem II and downstream electron acceptors during the polar night even though the low in situ net primary production levels measured in January prove that light was not sufficient to support any measurable primary production. Due to low temperatures resulting in low respiratory rates as well as the absence of photodamage during the polar night, maintenance of basic photosynthetic machinery may actually pose relatively low metabolic costs for algal cells. This could allow Arctic microalgae to endure the polar night without the formation of dormant stages, enabling them to recover and take advantage of light immediately upon the suns return during the winter-spring transition.

• MeSH
• bílkoviny řas metabolismus   MeSH
• fotosyntéza fyziologie   MeSH
• fotosystém II (proteinový komplex) metabolismus   MeSH
• fytoplankton fyziologie   MeSH
• mikrořasy fyziologie   MeSH
• roční období MeSH
• tma * MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Arktida MeSH
• Svalbard MeSH